Sony A9 vs Nikon D850

The Sony Alpha A9 and the Nikon D850 are two professional cameras that were announced, respectively,
in April 2017 and July 2017. The A9 is a mirrorless interchangeable lens camera, while the D850 is a DSLR. Both cameras are equipped with a full frame sensor. The Sony has a resolution of 24 megapixels, whereas the Nikon provides 45.4 MP. Read on to find out how these two cameras compare with respect to their body size, their sensors, their features, their input-output connections, and their reception by expert reviewers.

Body comparison: Sony A9 vs Nikon D850

The physical size and weight of the Sony A9 and the Nikon D850 are illustrated in the side-by-side display below. The two cameras are presented according to their relative size. Three consecutive perspectives from the front, the top, and the back are available. All width, height and depth dimensions are rounded to the nearest millimeter.

If the front view area (width x height) of the cameras is taken as an aggregate measure of their size,
the Nikon D850 is considerably larger (48 percent) than the Sony A9. Moreover, the D850 is substantially heavier (49 percent) than the A9. In this context, it is worth noting that both cameras are splash and dust-proof and can, hence, be used in inclement weather conditions or harsh environments.

The above size and weight comparisons are to some extent incomplete since they do not consider the interchangeable lenses
that both of these cameras require. Both cameras have similarly sized sensors, but DSLRs have a larger flange-to-focal plane distance than mirrorless cameras,
which imposes contraints on the optical engineering process and generally leads to bigger and heavier lenses.
You can compare the optics available for the two cameras in the Sony FE Lens Catalog (A9) and the Nikon Lens Catalog (D850). Mirrorless cameras, such as the Sony A9, have moreover the advantage that they have a relatively short flange to focal plane distance and can thus use many lenses from other systems via adapters.

Concerning battery life, the A9 gets 650 shots out of its NP-FZ100 battery,
while the D850 can take 1840 images on a single charge of its EN-EL15a power pack. The power pack in the A9 can be charged via the USB port, so that it is not always necessary to take the battery charger
along when travelling.

The table below summarizes the key physical specs of the two cameras alongside a broader set of comparators. If you would like to visualize and compare a different camera combination, just use the right or left
arrows in the table to switch to the respective camera. Alternatively, you can also navigate to the CAM-parator app and
make your selection from the full list of cameras there.

The price is, of course, an important factor in any camera decision. The manufacturer’s suggested retail prices give an idea on the placement of the camera in the maker’s lineup and the broader market. The D850 was launched at a markedly lower price (by 27 percent) than the A9, which puts it into a different market segment. Usually, retail prices stay at first close to the launch price, but after several months, discounts become available. Later in the product cycle and, in particular, when the replacement model is about to appear, further discounting and stock clearance sales often push the camera price considerably down. Then, after the new model is out, very good deals can frequently be found on the pre-owned market.

Sensor comparison: Sony A9 vs Nikon D850

The imaging sensor is at the core of digital cameras and its size is one of the main determining factors of image quality. All other things equal, a large sensor will have larger individual pixel-units that offer better low-light sensitivity, wider dynamic range, and richer color-depth than smaller pixels in a sensor of the same technological generation. Further, a large sensor camera will give the photographer additional creative options when using shallow depth-of-field to isolate a subject from its background. On the downside, larger sensors tend to be more expensive and lead to bigger and heavier cameras and lenses.

Both cameras under consideration feature a full frame sensor, but their sensors
differ slightly in size. The sensor area in the D850 is 1 percent bigger. They nevertheless have the same format factor of 1.0. Both cameras have a native aspect ratio (sensor width to sensor height) of 3:2.

In terms of underlying technology, both cameras are build around BSI-CMOS sensors.

With 45.4MP, the D850 offers a higher
resolution than the A9 (24MP), but the D850 has smaller individual pixels (pixel pitch of
4.35μm versus 5.94μm for the A9). Yet, the D850 is a somewhat more recent model (by 3 months) than the A9, and its sensor
might have benefitted from technological advances during this time that enhance the light gathering capacity of its pixel-units. Coming back to sensor resolution, it should be mentioned that the D850 has no anti-alias filter installed, so that it can capture all the detail its sensor resolves.

The A9 has on-sensor phase detect pixels, which results in fast and reliable autofocus acquisition even during video recording.

The Sony Alpha A9 has a native sensitivity range from ISO 100 to ISO 51200, which can be extended to ISO 50-204800.
The corresponding ISO settings for the Nikon D850 are ISO 64 to ISO 25600, with the possibility to increase the ISO range to 32-102400..

Consistent information on actual sensor performance is available from DXO Mark for many cameras. This service determines an overall sensor rating, as well as sub-scores for low-light sensitivity ("DXO Sports"), dynamic range ("DXO Landscape"), and color depth ("DXO Portrait"). Of the two cameras under consideration, the D850 has a markedly higher DXO score than the A9 (overall score 8 points higher), which will translate into better image quality. The advantage is based on 1.5 bits higher color depth, 1.5 EV in additional dynamic range, and 0.4 stops of reduced low light sensitivity. The adjacent table reports on the physical sensor characteristics and the outcomes of the DXO sensor quality tests for a sample of comparator-cameras.

Sensor Characteristics

Camera Model

Sensor Class

Resolution (MP)

Horiz. Pixels

Vert. Pixels

Video Format

DXO Portrait

DXO Landscape

DXO Sports

DXO Overall

Camera Model

Sony A9»

Full Frame

24.0

6000

4000

4K/30p

24.9

13.3

3517

92

Sony A9

Nikon D850«

Full Frame

45.4

8256

5504

4K/30p

26.4

14.8

2660

100

Nikon D850

Canon 5DS«»

Full Frame

50.3

8688

5792

1080/60p

24.7

12.4

2381

87

Canon 5DS

Canon 5DS R«»

Full Frame

50.3

8688

5792

1080/60p

24.6

12.4

2308

86

Canon 5DS R

Nikon D5«»

Full Frame

20.7

5588

3712

4K/30p

25.1

12.3

2343

88

Nikon D5

Nikon D810«»

Full Frame

36.2

7360

4912

1080/60p

25.7

14.8

2853

97

Nikon D810

Nikon D610«»

Full Frame

24.2

6016

4016

1080/30p

25.1

14.4

2925

94

Nikon D610

Olympus E-M1 II«»

Four Thirds

20.2

5184

3888

4K/30p

23.7

12.8

1312

80

Olympus E-M1 II

Panasonic GH5«»

Four Thirds

20.2

5184

3888

4K/60p

23.9

13.0

807

77

Panasonic GH5

Sony A7 III«»

Full Frame

24.0

6000

4000

4K/30p

25.0

14.7

3730

96

Sony A7 III

Sony A7R III«»

Full Frame

42.2

7952

5304

4K/30p

26.0

14.7

3523

100

Sony A7R III

Sony A6500«»

APS-C

24.0

6000

4000

4K/30p

24.5

13.7

1405

85

Sony A6500

Sony A7R II«»

Full Frame

42.2

7952

5304

4K/30p

26.0

13.9

3434

98

Sony A7R II

Sony A7S II«»

Full Frame

12.0

4240

2832

4K/30p

23.6

13.3

2993

85

Sony A7S II

Sony A7 II«»

Full Frame

24.0

6000

4000

1080/60p

24.9

13.6

2449

90

Sony A7 II

Sony A99«»

Full Frame

24.0

6000

4000

1080/60p

25.0

14.0

1555

89

Sony A99

Sony A77«»

APS-C

24.0

6000

4000

1080/60p

24.0

13.2

801

78

Sony A77

Many modern cameras are not only capable of taking still images, but also of capturing video footage. Both cameras under consideration are equipped with sensors that have a sufficiently high read-out speed for moving images, and both provide the same movie specifications (4K/30p).

Feature comparison: Sony A9 vs Nikon D850

Apart from body and sensor, cameras can and do differ across a variety of features. For example, the A9 has an electronic viewfinder (3686k dots), while the D850 has an optical one.
Both systems have their advantages, with the electronic viewfinder making it possible to project supplementary shooting information
into the framing view, whereas the optical viewfinder offers lag-free viewing and a very clear framing image. The adjacent table lists some of the other core features of the Sony A9 and Nikon D850 along with similar information for a selection of comparators.

Core Features

Camera Model

Viewfinder (Type or '000 dots)

Control Panel (yes/no)

LCD Size (inch)

LCD Resolution ('000 dots)

LCD Attach- ment

Touch Screen (yes/no)

Shutter speed (1/sec)

Shutter flaps (1/sec)

Built-in Flash (yes/no)

Built-in Image Stab

Camera Model

Sony A9»

3686

n

3.0

1440

tilting

Y

8000

20.0

n

Y

Sony A9

Nikon D850«

optical

Y

3.2

2359

tilting

Y

8000

9.0

n

n

Nikon D850

Canon 5DS«»

optical

Y

3.2

1040

fixed

n

8000

5.0

n

n

Canon 5DS

Canon 5DS R«»

optical

Y

3.2

1040

fixed

n

8000

5.0

n

n

Canon 5DS R

Nikon D5«»

optical

Y

3.2

2359

fixed

Y

8000

14.0

n

n

Nikon D5

Nikon D810«»

optical

Y

3.2

1229

fixed

n

8000

5.0

Y

n

Nikon D810

Nikon D610«»

optical

Y

3.2

921

fixed

n

4000

6.0

Y

n

Nikon D610

Olympus E-M1 II«»

2360

n

3.0

1037

swivel

Y

8000

18.0

n

Y

Olympus E-M1 II

Panasonic GH5«»

3680

n

3.2

1620

swivel

Y

8000

12.0

n

Y

Panasonic GH5

Sony A7 III«»

2359

n

3.0

922

tilting

Y

8000

10.0

n

Y

Sony A7 III

Sony A7R III«»

3686

n

3.0

1440

tilting

Y

8000

10.0

n

Y

Sony A7R III

Sony A6500«»

2359

n

3.0

922

tilting

Y

4000

11.0

Y

Y

Sony A6500

Sony A7R II«»

2400

n

3.0

1229

tilting

n

8000

5.0

n

Y

Sony A7R II

Sony A7S II«»

2400

n

3.0

1229

tilting

n

8000

5.0

n

Y

Sony A7S II

Sony A7 II«»

2400

n

3.0

1230

tilting

n

8000

5.0

n

Y

Sony A7 II

Sony A99«»

2359

Y

3.0

1229

full-flex

n

8000

6.0

n

Y

Sony A99

Sony A77«»

2359

Y

3.0

921

full-flex

n

8000

12.0

Y

Y

Sony A77

One feature that differentiates the A9 and the D850 is in-body image stabilization (IBIS).
The A9 reduces the risk of handshake-induced blur with all attached lenses, while the D850 has to rely on optical image stabilization
in OIS-equipped lenses to achieve the same effect.

The reported shutter speed and shutter burst refer to the use of the mechanical shutter. In addition, the A9 features
an electronic shutter, which makes completely silent shooting possible. However, this mode is less suitable for photographing moving objects (risk of rolling shutter) or
shooting under artificial light sources (risk of flickering).

The A9 writes its imaging data to SDXC or Memory Stick PRO Duo cards, while the D850 uses SDHC or XQD cards. Both cameras feature dual card slots, which can be very useful in case a memory card fails.

Connectivity comparison: Sony A9 vs Nikon D850

For some imaging applications, the extent to which a camera can communicate with its environment can be an important aspect in the camera decision process. The table below provides an overview of the connectivity of the Sony Alpha A9 and Nikon D850 and, in particular, the interfaces the cameras (and selected comparators) provide for accessory control and data transfer.

Input-Output Connections

Camera Model

Hotshoe Port

Internal Microphone

Internal Speaker

Microphone Port

Headphone Port

HDMI Port

USB Type

WiFi Support

NFC Support

Bluetooth Support

Camera Model

Sony A9»

Y

stereo

mono

Y

Y

micro

2.0

Y

Y

Y

Sony A9

Nikon D850«

Y

stereo

mono

Y

Y

mini

3.0

Y

Y

Y

Nikon D850

Canon 5DS«»

Y

mono

mono

Y

-

mini

3.0

-

-

-

Canon 5DS

Canon 5DS R«»

Y

mono

mono

Y

-

mini

3.0

-

-

-

Canon 5DS R

Nikon D5«»

Y

stereo

mono

Y

Y

mini

3.0

-

-

-

Nikon D5

Nikon D810«»

Y

stereo

mono

Y

Y

mini

3.0

Y

-

-

Nikon D810

Nikon D610«»

Y

mono

mono

Y

Y

mini

2.0

-

-

-

Nikon D610

Olympus E-M1 II«»

Y

stereo

mono

Y

Y

micro

3.0

Y

-

-

Olympus E-M1 II

Panasonic GH5«»

Y

stereo

mono

Y

Y

full

3.1

Y

-

Y

Panasonic GH5

Sony A7 III«»

Y

stereo

mono

Y

Y

micro

3.1

Y

Y

Y

Sony A7 III

Sony A7R III«»

Y

stereo

mono

Y

Y

micro

3.1

Y

Y

Y

Sony A7R III

Sony A6500«»

Y

stereo

mono

Y

-

micro

2.0

Y

Y

-

Sony A6500

Sony A7R II«»

Y

stereo

mono

Y

Y

micro

2.0

Y

Y

-

Sony A7R II

Sony A7S II«»

Y

stereo

mono

Y

Y

micro

2.0

Y

Y

-

Sony A7S II

Sony A7 II«»

Y

stereo

mono

Y

Y

micro

2.0

Y

Y

-

Sony A7 II

Sony A99«»

Y

stereo

mono

Y

Y

mini

2.0

-

-

-

Sony A99

Sony A77«»

Y

stereo

mono

Y

-

mini

2.0

-

-

-

Sony A77

Studio photographers will appreciate that the Nikon D850 (unlike the A9) features a PC Sync socket, so that professional strobe lights
can be controlled by the camera.

Both the A9 and the D850 are recent models that feature in their makers' current product line-up. The D850 replaced the earlier Nikon D810, while the A9 does not have a direct predecessor.

Review summary: Sony A9 vs Nikon D850

So what conclusions can be drawn? Is the Sony A9 better than the Nikon D850 or vice versa? The listing below highlights the relative strengths of the two models.

Advantages of the Sony Alpha A9:

Better moiré control: Has an anti-alias filter to avoid artificial patterns to appear in images.

Better studio light control: Has a PC Sync socket to connect to professional strobe lights.

More affordable: Was introduced into a lower priced category (27 percent cheaper at launch).

More modern: Was introduced somewhat (3 months) more recently.

If the number of relative strengths (bullet points above) is taken as a guide, the D850 emerges as the winner of the match-up (14 : 11 points). However, the pertinence of the various camera strengths will differ across photographers, so that you might want to weigh individual camera traits according to their importance for your own imaging needs before making a camera decision.

A9 11:14 D850

In any case, while the comparison of the spec-sheets of cameras can offer a general idea of their imaging potential, it says nothing about, for example, the handling, responsiveness, and overall imaging quality of the A9 and the D850 in practical situations. At times, user reviews, such as those published at amazon, address these issues in a useful manner, but such feedback is on many occasions incomplete, inconsistent, and unreliable.

Expert reviews: Sony A9 vs Nikon D850

This is why expert reviews are important. The table below summarizes the assessments of some of the best known camera review sites (cameralabs, dpreview, ephotozine, imaging-resource, photographyblog). The detailed reviews can be accessed by clicking on the site logo in the table header.

The review scores listed above should be treated with care, though. The ratings were established in reference to similarly priced cameras that were available in the market at the time of the review. Thus, a score needs to be put into the context of the launch date and the launch price of the camera, and rating-comparisons among cameras that span long time periods or concern very differently equipped models make little sense. Also, please note that some of the review sites have changed their methodology and reporting over time.

Other camera comparisons

Did this review help to inform your camera decision process? If you would like to see a different side-by-side camera review, just use the search menu below. There is also a set of direct links to comparison reviews that other users of the CAM-parator app explored.